When it comes to PCB etching, one of the most commonly used options to remove copper is Ferric Chloride (FeCl3) solution. Most of the methods described rely on submerging the copper clad board into a good quantity of etchant solution. To accelerate the process you are prompted to heat the solution and continuously agitate the bath. Although effective, this will take a rather long time to complete the process.
Alternately, the "Sponge Method" (with FeCl3) is amazingly fast (you can actually see the progress) and requires a very small quantity of etchant.
As with all FeCl3 etching methods, this must be carried out in a well ventilated space.
Step 1: The Sponge Method
The sponge method consists in wiping the copper clad board with a sponge saturated with FeCl3 solution. Any soft sponge will do. For small single sided boards I use a sponge designed for applying shoe polish which has a convenient plastic handle. For double sided boards, hold the board in your hand with protective gloves.
Step 2: Watch the Video for a Real-time Etching Demonstration
Step 3: How to Do It
For single sided boards, stick inside a saucer or low profile container with a loop of masking tape
Step 4: Pour a Very Small Quantity of FeCl3
Just enough etchant to cover the board.
Step 5: Etching
Gently wipe the board in all directions. In less than 2 minutes, your board is finished! .
Step 6: Final Step
Remove the board, and rinse in water to stop the etching process.
I made this PCB with the Heatless Toner Transfer method: